Tomato spotted wilt tosopvirus (TSWV) is a single taxonomic entity (genus Tospovirus: family Bunyaviridae). In 2015 it was proposed to change the name of the virus from Tomato spotted wilt virus to Tomato spotted wilt tospovirus (ICTV, 2015; Van Regenmortel et al., 2015). It has been ratified in 2016 for all the family of the Bunyaviridae.

3 - Is the pest already listed in a PM4 standard on the concerned host plant?

No

Conclusion:

Evaluation continues

4 - Are the listed plants for planting the main* pathway for the "pest/host/intended use" combination? (*: significant compared to others):

Yes

Conclusion:

Candidate

Justification:

TSWV has an extremely wide host range with more than 1 300 plants including agricultural crops, wild and weed species (Parrella et al., 2003; Peters, 2003), but the Council Directive 2000/29 is restricting measures to only 10 host plants. TSWV is a systemic pathogen and, as such, it is very efficiently transmitted by all vegetative multiplication techniques (EFSA-PLH, 2012). The virus is transmitted by thrips in a persistent propagative mode (Ullman et al., 1993; Wijkamp et al., 1993). Because of the persistence of TSWV in the vectors, the virus can be carried by infected plant material but also by viruliferous thrips, which can be present on a consignment that is infected with TSVW or even on consignments of non-host plants of the virus. The interception reports in EUROPHYT (very few) indicate that TSWV is found mostly in consignments of ornamentals and in 2011 and 2012 it has been reported four times on Lycopersicon esculentum. TSWV and viruliferous thrips are being transported in living planting material and will survive transport and storage as long as their hosts remain alive (EFSA-PLH, 2012). The plants for planting are a significant pathway compared to other pathways.

5 - Economic impact:

Are there documented reports of any economic impact on the host?

Yes

Justification:

TSWV infections in tomato occurring at an early stage in development result in severe stunting of plants, poor fruit setting and, when fruits eventually develop, fruits that are small and with yellow, brown or necrotic spots or rings (EFSA, PLH, 2012). TSWV causes yield and quality reductions and unappealing symptoms that render fruits unmarketable. While quantitative data on yield loss in crops and ornamentals are generally lacking, losses from TSWV diseases are considered very serious (Verhoeven and Roenhorst, 1994; Scholthof et al., 2011). TSWV is considered a very important pathogen of tomatoes, and severe losses have been encountered in crop production in Italy, Spain, Bulgaria and Greece. A similarly high impact on a range of other horticultural crops, such as pepper, potato, eggplant, lettuce and broad beans, is observed (EFSA, PLH, 2012). A great impact on tomato yield was reported by Moriones et al. (1998) in studies of natural TSWV infections in experimental plots in Northern Spain. Field experiments in Turkey, in which plots were naturally infected with TSWV, resulted in crop losses of up to 42 %, with an almost complete loss of marketable tomatoes (Sevik and Arli-Sokmen, 2012). Recently (2014 and 2015) TSWV infections affected tomato and pepper production (outdoor and indoor) in some Southern parts of Bulgaria.

What is the likely economic impact of the pest irrespective of its infestation source in the absence of phytosanitary measures? (= official measures)

Major

Is the economic impact due to the presence of the pest on the named host plant for planting, acceptable to the propagation and end user sectors concerned?

No

Conclusion:

Candidate

Justification:

6 - Are there feasible and effective measures available to prevent the presence of the pest on the plants for planting at an incidence above a certain threshold (including zero) to avoid an unacceptable economic impact as regards the relevant host plants?

Yes

Conclusion:

candidate

Justification:

7- Is the quality of the data sufficient to recommend the pest to be listed as a RNQP?

Yes

Conclusion:

Candidate

Justification:

CONCLUSION ON THE STATUS:

Recommended for listing as an RNQP - based on data.

8 - Tolerance level:

Is there a need to change the Tolerance level:

No

Proposed Tolerance levels:

Zero tolerance approach, based on visual examination and/or testing.

9 - Risk management measures:

Is there a need to change the Risk management measure:

Yes

Proposed Risk management measure:

(A) The site of production has been subjected to a monitoring regime and appropriate treatments to ensure effective suppression of populations of relevant thrips vectors (Frankliniella occidentalis and Thrips tabaci);
AND
(B) (a) No symptoms of Tomato spotted wilt tospovirus have been observed on plants at the site of production during the current growing period;
or
(b) Any plants at the production site showing symptoms of Tomato spotted wilt tospovirus during the current growing period have been rogued out and a representative sample of the plants to be marketed has been tested and found free from the pest.

REFERENCES:

EU COM (2016) Recommendation of the Working Group on the Annexes of the Council Directive 2000/29/EC – Section II – Listing of Harmful Organisms as regards the future listing of Tomato spotted wilt virus ;